What does interoperability mean?

At the WebCT Users Conference in San Francisco this past week my boss, Peter Siegel the CIO here gave a presentation join with Chris Vento of WebCT about interoperability. Chris started with the WebCT perspective, what they are doing and why it makes sense from WebCT's point of view to participate. Chris also talked about the similarity and differences between their proprietary connector, branded as PowerLinks, and the IMS sponsored standards based connector. Then Pete talked about the perspective from our campus point of view, emphasizing the interaction with other CIC schools some of which are principle players in the Sakai initiative, with other vendors, and with the Provost and other high level administrators on campus.

At my level, the issues are a little less abstract. The list includes the following:
(1) If the tool is not part of Vista, does it reside on its own separate server or on the Vista cluster?
(2) If the tool is not part of Vista, who administers the tool? Do we do that or does some other campus unit do that?
(3) If in (2) above the answer is some other campus unit, do we start to allow other campus units to administer within Vista itself?
(4) How are upgrades managed? Do we upgrade the tool at a different time than we upgrade Vista proper?
(5) Do standards matter if we are using other Vendor supplied tools? If the Vendors are willing to make their tools PowerLink compatible, do we care? In other words, will this be a criterion by which other vendor tools will be selected in the future?
(6) What things should we ask WebCT to develop within the Vista environment? Will we care in the future whether things are interoperable but separate tools versus fully integrated into the basic environment?
(7) Even if the tool is fully interoperable, does the integration of the tool with Vista entail substantial effort and cost?

At the same conference WebCT announced its approach to ePortfolios, with the first release coming out next spring. Seemingly a major selling point is the tight integration with Vista. So, obviously, we're not yet there with full interoperability.

When might we get there? That is the really big question.